It should be remembered that the use of non sync cameras, ie cameras that are not genlocked or accurately synchronised is less than optimal for stereoscopic 3D acquisition. Using a synchroniser on the cameras output will not eliminate or reduce the effects of having non sync cameras but it will allow the use of monitors or devices that require a synchronised input. The most common reasons to use non sync cameras are cost and availability, with video equipped DSLR’s or low cost camcorders being commonly used cameras. Vey often these will have HDMI or composite video outputs as opposed to the HDSDi outputs found on most professional HD video cameras.
1: Dual Input to 3D output converter with built in frame synchronisers.
2: Computer or Tablet device with suitable input devices and software.
Option 1, Dual Input to 3D output converter with built in frame synchronisers.
By connecting both cameras to a frame synchroniser/combiner it is possible to use a 3D monitor or television that would normally require a synchronised input. I have listed the adapters that I know to have built in synchronisers along with their input and output types below. Devices with an HDMI output will normal work with a consumer 3D TV.
MiraCube 3D Mini Converter (HDMI x 2 inputs, Single 3D HDMI out plus HDSDI out for each input).
Matrox MC100 (2x HDSDI inputs, single 3D HDMI output and Dual HDSDI output).
The Matrox MC100 can output an Anaglyph output on the HDMI or HDSDI outputs, so this can be connected to a conventional 2D monitor, particularly useful for field or location use with a small monitor. However it only has HDSDI inputs so you will need a pair of HDMI to HDSDI converters for use with DSLR’s. For this I recommend the Atomos Connect devices as these can be self powered and stacked together or the Black Magic Design mini converters.
Option 2, Computer or Tablet device with suitable input devices and software.
There may be other ways of doing this but the method I describe below works and is cost effective. It involves using a PC, Laptop or Tablet PC to synchronise a pair of inputs and display them as an Anaglyph display on the computers screen or a 3D display via the computers HDMI output.
A pair of Canon DSLR’s can be brought into reasonable sync by using a split trigger cable to take a still photo with both cameras after you have started recording. This resets the cameras shutters and they will run in reasonable sync for a few minutes after taking the still photo. However the output is still not genlocked so some form of synchronization is still required for monitoring.
One popular tool to use is Peter Wimmer’s Stereoscopic Multiplexer and Stereoscopic Player software on a PC, but even a laptop can be a bit bulky. As an alternative you can also use a Tablet PC. The best option I have found so far is an unbranded N450 10.2” Tablet PC that looks like a large I-Phone. It comes with Windows 7 pre installed. You may be able to get this working on other tablets too. Another option is the Archos 9 Tablet with the optional VGA/USB expansion adapter. The Archos has a dual core Intel Atom CPU, but it still a little lacking in horse power so there is some lag in the display and a frame size limit of 640×480, but it’s OK for getting a rig reasonably well aligned and very portable. The N450 10.2? I-Phone look alike will allow full SD 720×480 (720×576) resolution at full screen size. Here’s what you need to do to get it all going, these instruction will also work with a most reasonably current conventional Windows PC’s and Laptops or even a MacBook Pro running Windows under Parallels:
Pictures of the Un-Branded N450 10.2” Tablet PC (commonly listed on ebay and Amazon).
THE MOST IMPORTANT BIT:
Get a pair of EZCAP.TV EzCap 116 USB 2.0 capture cards. IT MUST BE THE EzCAP 116. Do not buy the generic EasyCap models, many of them will not work in pairs, it must be the 116. I strongly recommend getting the full retail boxed version, barcode No X0002X5LGT. I paid £19.00 GBP each for the ones I am using.
You will also need the expansion port adapter for the Archos 9 (windows 7 version) if you plan to use that.
Here are the installation steps:
1: On a PC or other computer copy the entire contents of the install CD Rom that comes with the EzCap to a USB memory stick.
2: Insert the memory stick into the tablet or PC and browse to it and double click on Autorun. First install the drivers. You should allow the PC to re-start after the install.
3: Again click on Autorun on the memory stick, now install Showbiz 3.5. You MUST install showbiz.
4: Go to 3dtv.at and download and install both Stereoscopic Multiplexer and Stereoscopic Player.
5: Unplug the memory stick and now plug in one of the EZCap devices to the USB port, connect a camera to the EzCap (in the case of a DSLR using the composite cable supplied with the DSLR. Windows should detect the EzCap and install the drivers, this can take quite some time, perhaps 10 minutes (go and have a coffee). If you get an unrecognised device error at this stage, ignore it.
6: Plug the second EzCap device into one of the ports on the Archos expansion box (you can’t plug them both into the expansion port or a USB hub, it won’t work, they must be on separate USB busses) or a second USB port on the tablet/PC. On the N450 I use the two USB ports on the left hand side for the EzCaps.
7: Run ArcSoft ShowBiz. When ShowBiz is running click on the capture tab. At the top of the capture window under “Source” select the first “USB 2861 Device” (may be labeled WDM 2861) Then set “Video Input” to “composite”. You should see the camera output on the screen. Now under “Source” select the second “USB 2861 Device” and select composite, now you should see the second cameras output.
8: Close the capture window and Quit ShowBiz.
9: Start Stereoscopic Multiplexer. The Configuration Wizard should start. For Left Capture device select the upper 2861 Device from the drop down list, for the right camera select the lower 2861 device. For both devices set the appropriate input standard, Pal-I for PAL and NTSC-M for NTSC. Click Next.
10: The maximum resolution the Archos 9 will support for two sources is 640×480 (Laptops should support full 720×576). Select this and then test that you can see each camera using the test left/right buttons. Check that 640×480 is selected before clicking next. The N450 Tablet will support 720×576.
11: Go with the defaults on this page, just click next.
12: Again keep the presets on this last page and click finish.
13: After a few moments you should now see both cameras outputs, displayed side by side. Quit Stereoscopic Multiplexer.
14: Once Stereoscopic Multiplexer has been configured it should remember these settings so you should not need to set it up again.
15: Start Stereoscopic Player. Under “File” select “Live View” and “Stereoscopic Multiplexer”. You should now be seeing both cameras. By using the “View” menu you can choose how to view the images, on the Archos9 “colour Anaglyph” will be the most useful for alignment and “side by side” to check relative exposure and colour balance. Note that if using a mirror rig you can do a horizontal flip of either camera via the “View” menu.
There is some lag in the image display, but it’s useable for alignment and checking. Higher performance PC’s will give better results, but are not as portable.